Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5618551-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
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The effective portion of net gain (loss) reclassified from accumulated other comprehensive income into income on derivative instruments designated and qualifying as hedging instruments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624171-113959

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4D
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624177-113959

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The effective portion of gains and losses (net) on derivative instruments designated and qualifying as hedging instruments that was recognized in other comprehensive income during the current period.

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Amount of realized and unrealized gain (loss) of derivative instruments not designated or qualifying as hedging instruments.

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Derivatives and Fair Value Measurements - Gains and Losses on Hedging Derivatives (Details) - Designated as Hedging Instrument - USD ($) $ in Millions	3 Months Ended			6 Months Ended	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Apr. 01, 2017	Sep. 30, 2017	Sep. 30, 2018
Successor
Derivative Instruments, Gain (Loss) [Line Items]
(Loss) gain realized in income on derivatives	$ (1.8)	$ 7.3		$ 7.0	$ (6.5)
Unrealized gain (loss) recognized in income on non-designated derivatives	0.3	(1.7)		1.5	(1.4)
Total (loss) gain recognized in income	(1.5)	5.6		8.5	(7.9)
Successor \| Foreign currency option contract \| Operating costs and expenses
Derivative Instruments, Gain (Loss) [Line Items]
(Loss) gain realized in income on derivatives	(1.8)	7.3		7.0	(6.5)
Unrealized gain (loss) recognized in income on non-designated derivatives	0.3	(1.7)		1.5	(1.4)
Total (loss) gain recognized in income	$ (1.5)	$ 5.6		$ 8.5	$ (7.9)
Predecessor
Derivative Instruments, Gain (Loss) [Line Items]
Loss reclassified from other comprehensive loss into income			$ (27.6)
Total (loss) gain recognized in income			(27.6)
Predecessor \| Commodity swap contracts \| Operating costs and expenses
Derivative Instruments, Gain (Loss) [Line Items]
Loss reclassified from other comprehensive loss into income			(11.0)
Total (loss) gain recognized in income			(11.0)
Predecessor \| Foreign currency option contract \| Operating costs and expenses
Derivative Instruments, Gain (Loss) [Line Items]
Loss reclassified from other comprehensive loss into income			(16.6)
Total (loss) gain recognized in income			$ (16.6)